enoob wrote:
Other than a CA to see whats happening when i ride and sending one to thud (still not kidding T) i consider the best "test" to be real world. bolt it to a bike ride and see what happens. bench testing only tells you what happens on the bench not to say i wont bench test BUT how fragile is it ? 98.9 percent efficient and 20Nm per pound is great and all but what if the first bump in the road or the kick stand melting through ashphalt tips the bike and the motor bends ? wheres your efficiency then huh ?

MitchJi wrote:
If one motor is clearly more outstanding than all the others they could qualify for something like a "Best in Show".

So, how is it clearly outstanding? Because it looks cool?

Since these are torque machines, then the highest torque density under continuous operation should win. The best idea to me was ES against all other groups so we can open source the build or several builds. It's that sharing aspect that make ES heads and shoulders above the rest. With tens of millions put on the road every year in China, the number working on the technical aspects of ebikes must number in the thousands, yet the open source approach is missing. Look at the result...pretty much crap and moderately efficient efficient machines with no good answer for multi-gearing and of questionable durability. I'm sure a number of posters here can do better going at it alone, but working together we can take a big step forward. To help satisfy the competitive need, how about top contributor and top builder awards?

Along the idea of an open source approach I'll pledge the purchase of one of the magnet sets, including shipping to whoever the group designates.

Regarding temps I guess I just want to see if the motor is really straining, if an eponential trend shows damaging heat iminent (temp ratings for the magnets) we'll shut it down. I was thinking non contact for ease.
I am also assuming that the builders will have plenty of bench runs on a submital before tourtureing their baby on a dyno

I have no issues with any of the parameters of this challenge & am trying not to dwell on the word "Win". As much as I would like to build the highest, tourqueiest, shinyest, gooderest motor this side of eternity, I still will have to give a bunch of credit to the forum as I suspect any one who participates will. I am thingking I have already won a huge prize just being able to contribute anything. If we happen onto an applicable design that will benifit the comunity here & abroad then the aknowledgmet will be enough. (untill the Nobel prize commitee calls )
The Kudo's are just frosting on the cake. & again the target will allways be moving. (next motor should allways be better shouldn't it?)

ok ok ok. Whatever the rules, guidelines, whatever, I'm game despite probability of middle of the road outcome. I just want to build a useful motor and would appreciate some hand holding. With stuff like as much copper as will fit as guidelines and not a clue as to how the firing sequence or coil layout of the most advanced motors with the overlapping coils work, this stuff is daunting to us noobs. Sure we can build a motor that works, but that's not the point. A bit of hand holding and guidance from you guys like Mile, LFP, Fechter, etc. will go a long way. Some of us hackers may not come up with the best motor by a long shot, but we might have a useful idea or two that contributes toward an optimum.

I am with you John,
I feel like I am in the deep end of the pool at times. The only thing I am confident of is the actual building the thing. If it actualy works will be a thrill, & if it makes Miles threasholds I will be jubilant.

Did you check out the links to the go brushless knowledge base? They have some great animations showing a "fireing order" of a typical motor. Once that sinks in, it gets easyer to imagine the sequence using different termination set ups (delta-Wye). as far as, "as much copper as you can get in there"....that is the best description I have heard. Smaller motors are at the disadvantage in that regard.(thanks MR obvious!) but really if you have any questions there is a ton of brain power here & there is a miriad of links to tech stuff in the axial flux discusion thread & some more in the mule1.1 thread(& a bunch of duplication) I am out to the foundry to cast some rotor bodies for the mule.

I was thinking like this: thre phases are trensfer phases to induce magnetic field in other three phases in rotor and to react with other three phases in stator. The rotor can then be ultra light and I plan to use only 1/4th of the dia for stator coils. So basicly I can have only "thicker rim"

I know I am in "hub" class with this design that is why I did not get involved here.

Like I said, larger motors do have an advantage. That's the reason for the kg limit. This is the non-hub motor forum

0.kg to kg should be the range that most people want to work within?

Unless some people realize they can get a much more Kw per $ in a ready made
package that will work efficiently from 100 watts to 5 Kw and weigh about 5 kg.
Besides 3 hall sensors, and controller a complete motor can be purchased for about $200. in a action or $329.95 Complete with 14 N-42-H
magnets on a balanced rotor ans a slection of stator windings to choose your Kv. A high torque motor of this type will also reduce the amount of reduction needed and will enhance over all efficiency without any expenses or losses in multi reduction chains, gears or multi speed hubs.

Like I said, larger motors do have an advantage. That's the reason for the 3kg limit. This is the non-hub motor forum

0.5kg to 3kg should be the range that most people want to work within?

Unless some people realize they can get a much more Kw per $ in a ready made
package that will work efficiently from 100 watts to 5 Kw and weigh about 5 kg.
Besides 3 hall sensors, and controller a complete motor can be purchased for about $200. Complete with 14 N-42-H
magnets on a balanced rotor.

Are you showing a picture of an alternator rotor PM retrofit kit? Don't those struggle to make 80% efficiency over about 1kw?

Each carcinogen vapor exposure includes a dice roll for cancer.

Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.

Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.

Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.

Like I said, larger motors do have an advantage. That's the reason for the 3kg limit. This is the non-hub motor forum

0.5kg to 3kg should be the range that most people want to work within?

Unless some people realize they can get a much more Kw per $ in a ready made
package that will work efficiently from 100 watts to 5 Kw and weigh about 5 kg.
Besides 3 hall sensors, and controller a complete motor can be purchased for about $200. Complete with 14 N-42-H
magnets on a balanced rotor.

Are you showing a picture of an alternator rotor PM retrofit kit? Don't those struggle to make 80% efficiency over about 1kw?

A little better efficiency than Miles motor (I designed) without adding internal gears. Just a 7 to 1 ratio 219 chain drive. Not a hub motor. The od of the rotor is about 1/8" larger than the one in Miles motor but each magnet pole is about 10 times the strength with two more poles.